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1.
ChemSusChem ; 17(10): e202301508, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38280139

RESUMO

Hole mobility is critical to the power conversion efficiencies of perovskite solar cells (PSCs). Organic small-molecule hole-transporting materials (HTMs) have attracted considerable interest in PSCs due to their structural flexibility and operational durability, but they suffer from modest hole mobility. On the other hand, inorganic HTMs with good hole mobility are inflexible in structural variation and exhibit unsatisfactory cell efficiency. In this study, a ligand BT28 and its zinc-based coordination complex BTZ30 were synthesized, characterized, and investigated as HTMs for PSC applications. The mixed-halide perovskites can be grown uniformly with large crystalline grains on both HTMs, which exhibit similar optical and electrochemical properties. However, it was discovered that the BTZ30-based solar cell exhibited an open-circuit voltage of 1.0817 V and a high short-circuit current density of 23.1392 mA cm-2 with a champion power conversion efficiency of close to 20 %. The performance difference between the two HTMs can be attributed to the difference in their hole mobilities, which is 63.31 % higher for BTZ30 than BT28. The comparison of non-metal and metal HTMs revealed the importance of considering hybrid structures to overcome some shortcomings associated with organic and inorganic HTMs and achieve high-performance PSCs.

2.
ACS Appl Mater Interfaces ; 15(26): 31675-31683, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37348057

RESUMO

Hole transport materials (HTMs) with appropriate energy levels and comprehensive passivation effects help to obtain highly efficient and stable perovskite solar cells (PSCs). Electron-deficient character-induced HTMs can generate varying energy level alignments near the HTM/perovskite interface. Herein, we report the synthesis and investigation of two new dipolar HTMs, WWC103 and WWC105, based on 2-(1,1-dicyanomethylene)rhodamine and 4-cynophenylacetonitrile acceptors, enabling high-efficiency mixed-cation mixed-halide perovskite solar cells. Apart from having different acceptors, these HTMs are built on a heterocyclic frame, which can provide passivation effects and improve the morphology of the perovskite layer. As a result, these dopant-free HTM-based solar cells show a high open-circuit voltage and good power conversion efficiency. Among both, the solar cell based on the HTM with 2-(1,1-dicyanomethylene)rhodamine exhibits a high open-circuit voltage of 1.09 V with a champion power conversion efficiency of over 20.51%. The improved performance of WWC103 over WWC105 (19.74%) is attributed to the new acceptor, which, in addition to providing good energy-level alignments and hole mobility, also holds the ability to passivate the defects. The findings suggest a new acceptor unit for constructing dopant-free HTMs for efficient PSCs.

3.
Acta Pharmaceutica Sinica ; (12): 3508-3518, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1004648

RESUMO

Tumor brings great threat to human public health. In recent years, incidence rate and mortality of tumor were rapidly increased in the world. Anti-tumor therapies have undergone the development of cytotoxic therapy, targeted therapy, and immunotherapy. Among them, tumor immunotherapy is rapidly developed and becomes an important anti-tumor therapy in recent years, although it also brings some related side effects. Tumor microenvironment (TME) is composed of immune cells, vascular vessels, fibroblasts, the extracellular matrix, etc. TME significantly affects the efficacy of immunotherapy. Macrophages in the TME are named as tumor associated macrophages (TAMs). Recently, increasing studies have shown that TAMs play an important role in the regulation of tumor immunity, especially in tumor immune surveillance and immune escape. Currently, more and more anti-tumor immunotherapy strategies targeting TAMs are at the development stage. Based on the important role of TAMs in the TME and their potential as therapeutic targets in tumor immunotherapy, we first reviewed the subtypes and functions of TAMs, as well as the roles of TAMs in tumors. Furthermore, we summarized the research progress on anti-tumor strategies targeting TAMs and the current status of drug targeting TAMs. The current review will provide new ideas and novel insights for tumor immunotherapy.

4.
Acta Pharmaceutica Sinica ; (12): 9-20, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-964303

RESUMO

Pancreatic cancer is a highly malignant tumor with a poor prognosis. It is very hard to treat pancreatic cancers for their high heterogeneity, complex tumor microenvironment, and drug resistance. Currently, gemcitabine plus nab-paclitaxel, capecitabine and FOLFIRINOX are standard chemotherapy for resectable or advanced metastatic pancreatic cancer. Considering the limited efficacy and toxic side effects of chemotherapy, targeted and immune drugs have gradually attracted attention and made some progress. In this article, we systematically reviewed the chemotherapeutic drugs, targets and related targeted drugs, and immunotherapy drugs for pancreatic cancer.

5.
Molecules ; 25(9)2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32380749

RESUMO

New D-π-A configured organic sensitizers featuring halogen-substituted oxindole-bridged acceptor units have been synthesized for dye-sensitized solar cells applications. Among fluorine, bromine, and iodine substitution, the cell based on bromine incorporated dye exhibited the highest efficiency. The oxindoles in these sensitizers were found to assist the electron injection through the chelation of their amide carbonyl groups to the TiO2 surface. This study provides an alternate approach for future rational dye design to gain excellent DSSC performance.


Assuntos
Corantes/síntese química , Oxindóis/síntese química , Bromo/química , Corantes/química , Flúor/química , Iodo/química , Estrutura Molecular , Oxindóis/química , Energia Solar
6.
Acta Pharmaceutica Sinica ; (12): 1718-1727, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-780312

RESUMO

The occurrence and development of tumors are closely related to the tumor microenvironment. Among them, tumor immune microenvironment and tumor metabolic microenvironment play important roles in tumor. Tumor immunotherapy is a way to kill tumor cells by activating the body's immune system. Tumor immunotherapy has shown good therapeutic effects in a variety of solid tumors. In recent years, significant progress has been made in tumor immunotherapy. The Warburg effect indicates that tumor cells use aerobic glycolysis to acquire energy. In the tumor, the energy metabolism pathway is abnormal, and the tumor microenvironment can induce the reprogramming of tumor cell metabolism. Therefore, targeting tumor metabolism is also of great significance for tumor treatment. In this paper, we reviewed the research progress of drug targets related to tumor immunology and tumor metabolism in recent years, as well as the progress of drug development.

7.
Dalton Trans ; 47(25): 8356-8363, 2018 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-29897066

RESUMO

New heteroleptic Ru(ii) complexes consisting of pyridylimine as an ancillary ligand were synthesized and characterized for applications in dye sensitized solar cells. Complexes with cis and trans configurations around the central ruthenium metal were obtained using simple synthetic protocols by varying the substituents on the pyridylimine ligands. The geometries of these complexes were confirmed by single crystal X-ray analysis. The effect of the difference in the configurations of these complexes on their device performances was studied and the sensitizer with a trans arrangement around the metal showed a higher overall conversion efficiency (η) of 7.27% than that of the cis configured complex (η = 2.04%).

8.
J Nanosci Nanotechnol ; 18(2): 967-975, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448521

RESUMO

TiO2 nanocubes were synthesized via hydrolysis condensation of titanium tetra-isopropoxide (TTIP) in aqueous media, followed by hydrothermal treatment with ammonium salts. Various ammonium salts with different alkyl chain such as ammonium hydroxide (NH4OH), tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH) and tetrabutylammonium hydroxide (TBAH) were investigated. The crystalline phase, shape, and morphology of TiO2 nanocubes were studied by XRD, TEM, and SEM analysis. These TiO2 nanocubes were pure anatase phase and tended to assemble with well-ordered and close-packed domains. Both alkyl chain length of ammonium salts and hydrothermal duration affected the TiO2 nanocube formation process. The ammonium salts with longer alkyl chain formed TiO2 nanocubes in shorter hydrothermal time and offered the smallest particle size. The above TiO2 nanocubes were applied as photoanode materials in N719 anchored dye-sensitized solar cells and one of the cells exhibited the maximum power conversion efficiency of 7.85%.

9.
Inorg Chem ; 56(21): 12987-12995, 2017 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-29019659

RESUMO

We report the synthesis, characterization, and photovoltaic properties of four ruthenium complexes (CI101, CBTR, CB111, and CB108) having various N-heterocyclic carbene ancillary ligands, pyridine-imidazole, -benzimidazole, -dithienobenzimidazole, and -phenanthroimidazole, respectively. These complexes were designed to investigate the effect of extended conjugation ordained from ring fusion on the power conversion efficiencies of the solar cells. The device sensitized by CB108, the pyridine-phenanthroimidazole conjugated complex, showed an improved efficiency (9.89%) compared to those of pyridine-benzimidazole conjugated system (CBTR, 9.72%) and the parent unfused ring system (CI101, 6.24%). Surprisingly, the sulfur-incorporated pyridine-dithienobenzimidazole system (CB111, 9.24%) exhibited a little lower efficiency than that of N719 (9.41%). The enhanced photovoltaic performance of CB108 was mainly attributed to the increase in electron lifetime and diffusion length confirmed by the electrochemical impedance spectroscopy.

10.
Org Lett ; 18(14): 3386-9, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27384258

RESUMO

Novel organic pyridinium ylide sensitizers (NO109-111) consisting of various anchoring groups were synthesized and characterized for applications in dye sensitized solar cells. Compared with the pyridine-N-oxide dye (NO108), the ylide sensitizers with strong electron-withdrawing acceptors exhibited dominant ultraviolet absorption properties and efficient binding abilities to the TiO2 surface. Among these dyes, the pyridinium ylide NO111 sensitized solar cell showed the highest efficiency (5.15%), which was improved to 7.41% by employing coadsorbent chenodeoxycholic acid.

11.
Org Lett ; 15(17): 4292-5, 2013 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-23964726

RESUMO

Two novel oxindole sensitizers have been synthesized for dye-sensitized solar cell applications. These new dyes can provide an additional pathway to inject electrons into the photoanode through the partial chelation of their amide carbonyl groups to the TiO2 surface. Incorporation of an electron deficient pyridine in the acceptor of the TI125 dye was found to enhance the photovoltage and conversion efficiency of the cell.

12.
Chem Asian J ; 8(9): 2196-203, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23832840

RESUMO

A new type of carbene-based ruthenium sensitizer, CB104, with a highly conjugated ancillary ligand, diphenylvinylthiophene-substituted benzimidazolepyridine, was designed and developed for dye-sensitized solar cell applications. The influence of the thiophene antenna on the performance of the cell anchored with CB104 was investigated. Compared with the dye CBTR, the conjugated thiophene in the ancillary ligand of CB104 enhanced the molar extinction coefficient of the intraligand π-π* transition and the intensity of the lower energy metal-to-ligand charge-transfer band. However, the incident photon-to-current conversion efficiency spectrum of the cell anchored with CB104 (0.15 mM) showed a maximum of 63 % at 420 nm. The cell sensitized with the dye CB104 attained a power conversion efficiency of 7.30 %, which was lower than that of the cell with nonconjugated sensitizer CBTR (8.92 %) under the same fabrication conditions. The variation in the performance of these two dyes demonstrated that elongating the conjugated light-harvesting antenna resulted in the reduction of short-circuit photocurrent density, which might have been due to the aggregation of dye molecules. In the presence of a coabsorbate, chenodeoxycholic acid, the CB104-sensitized cell exhibited an enhanced photocurrent density and achieved a photovoltaic efficiency of 8.36 %.

13.
J Vet Med Sci ; 74(11): 1439-46, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22785246

RESUMO

This report describes an enzyme-linked immunosorbent assay (ELISA) for tissue-bound metabolite 3-amino-5-morpholinomethyl-2-oxazolidinone (AMOZ) and the application to residue analysis in cultured fish samples. The residue is monitored as a marker for the drug furaltadone. The assay enables the detection of protein bound AMOZ in the form of a 2-nitrophenyl derivative (2-NP-AMOZ) in sample supernatant or extract after acid hydrolysis and derivatization with o-nitrobenzaldehyde. Polyclonal rabbit antibodies were produced with a new immunogen hapten, 2-NP-HXA-AMOZ. The new ELISA had adequate analytical sensitivity (IC(50) value 0.325 µg kg(-1); limit of detection 0.1 µg kg(-1)) to determine a trace of AMOZ residue and had a high selectivity. Recoveries of AMOZ fortified at the levels of 0.1, 0.5 and 1.0 µg kg(-1) ranged from 89.8 to 112.5% with coefficients of variation of 12.4-16.2% over the range of AMOZ concentrations studied. The results obtained with the ELISA correlated well with those obtained by commercial test kits for 150 tested samples (r=0.984). The results suggest that the developed ELISA is a highly specific, accurate, and sensitive method suitable for high throughput screening for AMOZ residues.


Assuntos
Biomarcadores/análise , Resíduos de Drogas/análise , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/veterinária , Peixes/metabolismo , Ensaios de Triagem em Larga Escala/veterinária , Morfolinas/análise , Oxazolidinonas/análise , Animais , Benzaldeídos , Biomarcadores/metabolismo , Resíduos de Drogas/química , Resíduos de Drogas/metabolismo , Ensaios de Triagem em Larga Escala/métodos , Concentração Inibidora 50 , Estrutura Molecular , Morfolinas/química , Morfolinas/metabolismo , Nitrofuranos , Oxazolidinonas/química , Oxazolidinonas/metabolismo , Sensibilidade e Especificidade
14.
Nanoscale Res Lett ; 7(1): 147, 2012 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-22353282

RESUMO

The vertically orientated TiO2 nanotube array (TNA) decorated with TiO2 nano-particles was successfully fabricated by electrochemically anodizing titanium (Ti) foils followed by Ti-precursor post-treatment and annealing process. The TNA morphology characterized by SEM and TEM was found to be filled with TiO2 nano-particles interior and exterior of the TiO2 nano-tubes after titanium (IV) n-butoxide (TnB) treatment, whereas TiO2 nano-particles were only found inside of TiO2 nano-tubes upon titanium tetrachloride (TiCl4) treatment. The efficiency in TNA-based DSSCs was improved by both TnB and TiCl4 treatment presumably due to the increase of dye adsorption.

15.
Dalton Trans ; 40(25): 6765-70, 2011 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-21597610

RESUMO

A new series of N-heterocyclic carbene (NHC)-pyridine ruthenium complexes incorporating a carbene unit as an ancillary ligand were designed and successfully synthesized by using simple synthetic methods. The photophysical, electrochemical and photovoltaic properties of these NHC-pyridine based ruthenium complexes were investigated. These complexes showed photoelectric conversion efficiencies in the range of 6.43 ∼ 7.24% under the illumination of AM 1.5 (100 mW cm(-2)). Interestingly, the modifications on the ancillary ligand of these sensitizers by removal of an alkoxyl group and replacement of the octyl chain with a 3,5-difluorobenzyl group showed a 13% increase in the conversion efficiency for the CifPR dye. These results demonstrated that structural modifications on the NHC-pyridine ancillary ligand of ruthenium complexes results in dye-sensitized solar cells exhibiting a comparable cell performance to that obtained using the standard N719 dye.

18.
J Agric Food Chem ; 57(13): 5687-92, 2009 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-19526989

RESUMO

A sensitive and specific polyclonal enzyme-linked immunosorbent assay (ELISA) for the determination of tissue-bound metabolite 3-amino-2-oxazolidinone (AOZ) is described. The procedures allow for the detection of protein-bound AOZ in the form of a 2-nitrophenyl derivative (2-NP-AOZ) in the sample supernatant or extract after acid hydrolysis and derivatization with o-nitrobenzaldehyde. The polyclonal rabbit antibodies were produced with the immunogen hapten, 2-NP-HXA-AOZ, and the 50% inhibition values (IC(50)) of 0.14 microg kg(-1) of AOZ was achieved with the most sensitive antibody A0505. The mean lower detection limit of the ELISA method is about 0.025 microg kg(-1). According to the test preparation record, the detection limit is 0.1 microg kg(-1), which is well below the minimum required performance limits (MRPLs) for tissue-bound residues of AOZ at 1 microg kg(-1) in the European Communities. In the present study, we investigated the use of homemade ELISA, a new immunoassay, to monitor the presence of the furazolidone marker residue in 370 samples of cultured fish. Adopting 0.3 microg kg(-1) AOZ as a cutoff value, the ELISA has a sensitivity of 100% and a specificity of 98.5% versus high-performance liquid chromatography-mass spectrometry (HPLC-MS) at a cutoff of 0.3 microg kg(-1) and gives no false-negative rate results. From the practical point of view, the homemade kit could be advantageously used for the screening of large groups of animal-edible tissue samples and the kit employed has good reliability even in routine application for the control of the illegal use of the drug.


Assuntos
Antibacterianos/análise , Resíduos de Drogas/análise , Ensaio de Imunoadsorção Enzimática/métodos , Peixes , Oxazolidinonas/análise , Alimentos Marinhos/análise , Animais , Aquicultura , Sensibilidade e Especificidade
19.
J Chromatogr A ; 1127(1-2): 246-53, 2006 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16806245

RESUMO

The synthesis and determination of persistent dicarboxylic metabolites of alkylphenol polyethoxylates (NPEOs), carboxyalkyl phenoxy ethoxy carboxylates (CAPECs), are investigated. The synthesized CAPECs have three and four carbon atoms and a carboxyl group in the alkyl chain side, and a carboxymethoxy acid group in its para-position (expressed as CA(3)P1EC and CA(4)P1EC in their abbreviation). The synthesis was successfully accomplished via a four-step reaction sequence that started from 4-fluoroanisole. After propylation by a propanol/acetyl chloride procedure, the derivatives of synthesized CA(3)P1EC and CA(4)P1EC were separated and identified by GC-MS with electron impact ionization (EI). The most abundant characteristic ions were produced by benzylic cleavages of carboxyalkyl chain to yield [M-87](+), corresponding to ions of m/z 235 for CA(3)P1EC and m/z 249 for CA(4)P1EC. Recoveries of synthesized CA(3)P1EC and CA(4)P1EC in various spiked water samples ranged from 82 to 92% with relative standard deviations (RSD) lesser than 7%. The limits of quantitation (LOQ) of CA(3)P1EC and CA(4)P1EC were estimated to be 0.005 and 0.01 microg/l in 100ml of water samples, respectively. The concentrations of CA(4)P1EC residues were detected in the aquatic environment ranging from n.d. to 3.24 microg/l. The results show that the synthesized CA(4)P1EC has been successfully applied to more accurately determine the concentrations of CA(4)P1EC residues in water samples.


Assuntos
Ácidos Dicarboxílicos/síntese química , Etilenoglicóis/síntese química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Ácidos Dicarboxílicos/análise , Etilenoglicóis/análise , Polietilenoglicóis/análise , Polietilenoglicóis/síntese química , Sensibilidade e Especificidade , Poluentes Químicos da Água/análise
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